Speed. It’s one of the most revered qualities in all of athletics. Regardless of your sport, its likely that you need some kind of speed in order to be successful. In most popular sports, including football, basketball, hockey, soccer, martial arts, and track & field, speed is essential.
However, what most people may not realize is that it isn’t just speed alone that ensures success. In these so-called anaerobic sports, the athlete is required to generate repeated bursts of maximal force. These athletes need to be able to pair their speed with their strength. In other words, they must be able to display their strength quickly.
To that end, there are specialized methods of training that can be used both before and during the season to develop and maximize this ability, which is known generally as speed-strength. Speed-strength takes on a variety of forms and has uses in virtually any sport; these will be discussed later.
In terms of training, some coaches and experts would have it that the Principle of Specificity is held to its utmost; that is, only the exact skill of the sport can have any carryover to the sport. Going by this ideology, weight training is relegated to a role as a general means of increasing strength, with no use in preparing the athlete for the actual sport.
The other point of view proposes that some movements are specific to skills more than others. Training, then, is a matter of using the proper methods and the proper exercises. Additionally, the timing of those methods exercises in the different phases of training can have an impact on the overall performance of the athlete.
This article, as if it weren’t obvious, will be written from the perspective of the latter; it will discuss speed-strength, as well as the methods of speed-strength training, and will wrap up with a discussion on how to properly incorporate those methods into athletic preparation.
What is explosiveness exactly? The term has come into vogue in recent years as Western coaches have discovered the methods employed by the old Soviet and Eastern Bloc exercise scientists. However, it seems that very few actually know what the term means, let alone what concepts it encompasses or how to apply it.
Simply described, explosiveness is the ability to create force quickly. This is most commonly referred to as “power.” In classical physics, power is defined as force times velocity, or rate of work performed. However, power is only part of the issue.
It is possible for a movement to be explosive without being externally fast- as in the case of a slowly moving barbell in a maximum attempt, for example. To understand how this can be, we must first define the underlying concepts. Similar to power is rate of force development (RFD). Rate of force development is a curve showing how force develops and diminishes over a given time interval. A movement with rapidly developed force will have a steeper curve than a movement with a slower development, as the force is developing over a shorter time period.
A high RFD will always accompany a powerful movement, as both require force to be developed quickly. However, as noted above in the example of a maximal barbell lift, a high RFD does not always equate to external power. You can move slowly and still be considered “explosive;” the key to remember here is that force generated by the muscles does not equate on a one to one basis with the speed displayed in a given motion. You can generate force quickly and still not cause any fast movement.
Explosive strength can be defined as the maximum value of the RFD curve. In other words, the greatest amount of force you generate in a movement is the value of “explosive strength,” the same way that the maximum force you can create voluntarily is defined as maximum strength. This value is not dependent upon the total strength available, though. It is simply the highest force displayed in the given movement, against the given resistance. Since time is a component as well, it would be better to say that explosive strength is simply the “peak force generated in the shortest possible time.”
Beyond that, you can divide the “upward” phase of the RFD curve, the portion when force is building up to the maximum value, into two distinct phases: starting strength and acceleration strength. Starting strength is the phase when force is being developed before there is any external motion. Acceleration strength takes over when the movement begins and continues to increase unitl the maximum force is reached. When a barbell is lifted, some force is generated before the movement begins. Once the force required to move the bar is reached, the bar begins to move. Assuming the intent of speed is present, thus assuring a high RFD, the bar will keep moving faster as more force is applied during the lift.
Again it is important to note that RFD is separate from external movement. This is key because force can be developed with little if any visible motion, as is the case in isometrics. If the force created is not enough to overcome gravity, the bar will not move. The implications of this are as noted before: fast movements are always explosive, but explosive movements are not always fast.
The concepts of “speed-strength” and “strength-speed” are often used in a similar context, though they are really conditional terms for external power. Speed-strength (and strength-speed) is defined as “any capacity that contains both a force and speed component to the muscular actions (Young 1993).” In this case, as opposed to explosiveness, external power is the critical component.
The differentiation between speed-strength and strength-speed is the loading. Speed-strength is a power generated from a light resistance; strength-speed is power generated with a heavy resistance.
Reactive Ability and the Stretch-Shortening Cycle
The stretch-shortening cycle is a physiological mechanism whereby the kinetic energy of a mechanical stretch is stored in the elastic connective tissues during a rapid eccentric action, held for a brief interval (the amortization phase), then immediately released during the subsequent concentric action. This so-called stretch reflex can last up to four seconds, thus contributing some assistance to all but the slowest motions (Siff 2000). It is best exploited with fast, instantaneous reversals that minimize the amortization interval when seeking to develop explosive strength.
Reactive ability is closely related to explosive strength, but is the specific neuromuscular quality of exploiting the stretch reflex, rapidly generating force after a mechanical stretch. While it is similar to explosiveness, it is a discrete motor quality that requires its own training.
Methods of Training
Maximal and Dynamic Effort Methods
As defined by Zatsiorsky, the maximal and dynamic-effort methods are two of the three possible means of increasing muscular tension. Maximal effort involves using heavy loads (85%+) for 1-6 reps, while the dynamic effort method prescribes loads of 60% or less, accelerated as quickly as possible (Zatsiorsky 1995).
Speed-strength can be developed by a fairly wide variety of training methods within those broad definitions. The general prescriptions are as follows:
Heavy load training (“strength-speed”)
- Effective for the development of various speed-strength qualities.
- Incorporated with an effort to produce explosive movement speed, if maximum strength-speed is expected.
- Produces increases in fast twitch fiber size as well as neural adaptations, especially intra-muscular coordination.
- Heavy load training (80-90%) should be emphasized during the late preparation phases.
Light load training (“speed-strength”)
- Effective for the development of various speed-strength qualities
- Should be highly sport specific to maximize potential benefits. These exercises are usually performed better in the field than in the weight room.
- Yields relatively minor fast twitch fiber hypertrophy but good development of inter-muscular coordination and therefore, good transfer to specific sports movements.
- Emphasis during the pre-competition phase in an attempt to convert general qualities to the specific speed-strength qualities required in the sport (Young 1993).
As you can see, the prescriptions are different for each training goal, for each training phase, and for each activity. Differing training protocols should be used during preparatory and competitive phases, according to the goals of the moment and the specific capabilities of the athlete.
During the general preparatory phase, a more well-rounded development of strength should be emphasized. This would include heavy load strength-speed/RFD training, which would be analogous to maximal-effort training. Explosive strength is best developed using the light load training.
As related to the discussion of RFD and power above, Zatsiorsky notes that a strong athlete is not always powerful, but a powerful athlete is always strong. The ability to generate maximal force is key to both explosive strength and speed-strength. Learning to display that force quickly is the key.
The two methods should be used in conjunction. While the maximal effort method recruits high-threshold motor units, the dynamic method allows more motor units to be recruited voluntarily. Thusly the two work in concert.
RFD is highly specific to the load and the movement. However, as seen above, speed-strength, especially when the movement is carefully selected to emulate the sporting action, has a high carryover. As with all training prescriptions, the emphasis progresses from general to specific throughout the cycle; the qualities developed during the preparatory phase, ie heavy-load speed-strength, can later be harnessed to develop subsequent, specific qualities.
This method is commonly called plyometrics by most Western sources. Shock training seeks to exploit the stretch reflex to its fullest by quickly imposing and reversing large loads. This develops explosive strength and reactive ability.
The most common examples are jumps for the lower body and medicine ball throws for the upper body. However, any method that uses a quickly imposed load that is immediately reversed falls under this category. It is not hard to conceive of many ways to implement such an approach with the equipment in most gyms, let alone by personal design.
Accentuated Eccentrics and Ballistics
The techniques of accentuated eccentrics and ballistics work on the stretch reflex principle as well. However, they differ from shock methods in that they use deliberate acceleration of weights.
Accentuated eccentrics involve the intentional, controlled acceleration of the eccentric phase of a movement. This generates a large amount of force, which activates the stretch reflex. Accentuated ballistics use the same concept with an immediate, accelerated reversal. Due to their force generation, both methods are useful for neural stimulation.
Elastic bands can greatly aid in both forms of training, as they accelerate the eccentric component of any given movement.
In some ways almost contrary to the shock method, static-dynamic training seeks to minimize the involvement of the stretch reflex by pausing a movement in the lengthened state. This pause allows the stretch reflex to dissipate, at which point the movement is reversed as quickly as possible.
In execution, the static-dynamic method has been shown effective in such examples as:
- A 2-3 second isometric contraction at 80% of max is held followed by an explosive concentric with 30% of max.
- Using a constant load of 75-80% max for both the paused and dynamic component (Siff 2000).
These may not seem to belong here, as the very word isometric means “without motion.” However, isometric contractions do have the ability to expose the body to incredibly heavy loads.
A factor that few people take into account is that isometrics, like any force-generating action of the body, have an RFD curve of their own. That is, the force involved takes time to build up, maintain, and drop off. Isometrics, like dynamic movements, can be “explosive.” If isometric exercises are executed with emphasis on the speed of developing force, they can be as effective for developing explosive strength as dynamic exercises, due to the steepness of the RFD curve and the magnitude of the tension. Isometric actions can be divided into voluntary isometrics and reflexive isometrics; reflexive isometrics are caused by the reflex response of the muscles during the amortization phase of a quick movement (Siff 2000).
The Strength Deficit
The strength deficit is defined as the difference between maximal strength, which is voluntary effort, and absolute strength, which is the maximal involuntary effort the athlete can produce in the same action.
While the strength deficit is hard to assess, the closest one can approach involuntary recruitment of as many muscle fibers in a given task is to force the body to react by reflex action to a suddenly imposed load (such as a plyometric, a ballistic motion, or even an “explosive isometric”). If there is a small difference between the sudden loading and the athlete’s voluntary capacity, this suggests that training focuses more on nervous stimulation via the use of shock and ballistic methods. If the deficit is large, then strength and hypertrophy training with 5RM to 8RM loads using methods such as CAT (compensatory activation training) is more suitable (Siff 2000).
Essentially, speed-strength should be produced by maximal neural stimulation in those individuals with a high deficit. For those with a small deficit, speed-strength is best produced by using sub-maximal loads to create hypertrophy, followed by maximal efforts with heavy loads (Siff 2000).
Application and Planning
The purpose of this article is not to discuss periodization. However, planning of athletic training, even if on a cursory level, is required in order to implement speed-strength training properly in the context of a sport program. Therefore, periodization must be discussed in some degree in order to provide context.
The macrocycle is a unit of planning that encompasses an entire training period, for our purposes consisting of a preparatory and competitive phase. The general trend is always from general to specific, from high volume to low, and from low intensity to high, though the individual undulations in those trends can vary at any level. From workout to workout, week to week, phase to phase, there will always be upward and downward trends, not simply a smooth line depicting the progression.
It should be noted that even the preparatory and competitive phases are sub-divided into multiple smaller phases; each phase can last quite a long time, with multiple blocks of training emphasis within each one.
The general preparation phase for speed-strength sports encompasses a very broad spectrum and relatively high volume of training methods. During this phase, general strength training is performed. Exercises need not, and perhaps should not, resemble the sporting action at all. Higher reps with submaximal loads and other methods used to induce muscular hypertrophy may be used, in conjunction with maximal effort and heavy speed-strength training.
General aerobic and anaerobic-endurance work is performed as needed. While the overall training volume is high, the amount of work devoted to technique and special strength training is very limited.
In contrast to the general phase, the special preparation phase, also called the competitive phase, begins to move away from the generalized work. Technique and special strength/endurance take precedence, with general strength training and endurance training performed only rarely. The overall volume is lowered, with more emphasis placed on to the specific form of training (intensification).
It is during this phase that the general qualities developed previously are honed into the skills required under competitive conditions.
While the preparatory phase will increase muscular strength and hypertrophy, in and of itself it cannot improve speed. The increased volume and lack of direct work will in fact cause a reduction in speed. However, the increased neural skill and hypertrophy do provide a foundation for subsequent speed-strength training.
After a period of adequate restoration, the volume is dropped sharply and more specific forms of training are implemented under competitive conditions. Using the after-effects of the general prep phase, the special prep phase is able to develop the athlete in excess of what it might have otherwise (Yessis 2003).
When implemented properly, combining general strength training with special strength training for sport, the result is not only a larger and stronger athlete, but one who is equally faster.
Training for speed, and specifically for speed applied forcefully, is a separate and unique means of training that is related to maximal strength, yet still a class of discrete motor qualitities. Developing speed-strength and reactive ability is key to the success of practically all athletes, and can be a useful skill for athletes interested in developing strength, due to the unique adaptations it imposes on the neuromuscular systems in the body.
Hopefully any arguments about specificity were sufficiently covered in the article above; that is merely a function of appropriate training. However, another issue often raised with fast and/or explosive training is the supposed risk of increased injury. Unfortunately, this risk is not substantiated by either injury statistics, which show Olympic Weightlifters having a lower risk of injury than practically any other athletes, nor by any biomechanical analysis of the movements.
Such risk is predicated upon the notion that the connective tissues can only handle a certain amount of force at any one time. Since fast movements involve more force, they are therefore more prone to causing injury. That analysis is limited to a very basic, and ultimately incorrect, understanding of biomechanics and the body’s function.
The connective tissues are not static structures. They change according to mechanical and thermal stresses imposed upon them. This dynamic character makes them highly resilient to external forces.
Technique is another factor to consider. The strength of connective tissues is displayed quite often in running, jumping, throwing, and other similar exercises, where the forces encountered greatly exceed anything encountered even in Olympic Weightlifting. It is exceedingly rare for any injury to be encountered when proper technique is applied. Injuries generally only occur when technique breaks down. It is important to note that even slow submaximal movements can carry a risk of injury. The correlation between force and injury is not direct by any means.
Above and beyond all of those factors is the simple issue that, like any tissue, the connective tissues strengthen and adapt to stresses imposed upon them. Any properly-applied program would gradually implement and increase the loading involved for any means of training, so as to minimize the risk of injury. Speed-strength training is no different.
Written by Matt Perryman
Discuss, comment or ask a question
If you have a comment, question or would like to discuss anything raised in this article, please do so in the following discussion thread on the Wannabebig Forums – Training for Speed-Strength and Explosiveness discussion thread.
Siff, MC. Supertraining. 2000 5th Edition. Supertraining Institute, Denver, USA.
Verkhoshansky, YW. 1977 Fundamentals of Special Strength Training in Sport. Fizkultura I Sport Publishers, Moscow.
Yessis, M. Re: Sports Specific Movements, and about Science Worries. Fri Aug 29, 2003
Young, W. Training for Speed/Strength: Heavy loads vs. light loads. 1993 NSCA Journal. 15(5):34-42.
Zatsiorsky, VM. Science and Practice of Strength Training. 1995 Human Kinetics, Champaign, IL.